At the beginning of the second millenium of Christianity there was a crisis in Europe that arose from the discrepancy between the populace's notion of what a religious life should be and the way of life it saw being led by members of the Church hierarchy. The teachings of Christianity led people to believe that the ideal life was one of material poverty and spiritual devotion; the life of the apostles. But the Church was wealthy and few priests strove for the apostolic life. Worse yet there were some priests who led dissolute lives contrary to the precepts of Church. The common people could not believe that such individuals, even though ordained by the Church, could perform sacred services. The Church's position was that no matter what the personal behavior of a priest was, if he was ordained by the Church any ceremony performed by him was just as valid as one performed by a saintly priest. The heresies of the time arose because the people accepted the precept that it was a necessary condition for a priest to lead a proper life and he should strive for the apostolic ideal. From this position it was a small step to the position that a individual who led an apostolic life was better suited to act as priest than some who was ordained but did not strive for the apostolic life.

The Cathars were treated as heretics of Christianity by the Catholic Church, but the origin of the religion of the Cathars was quite strange. The doctrine of the Cathars had its origins in the religion of the Bogomils in the Balkans. This doctrine was dualistic in nature which identified it as an alien religion rather than merely a heresy. Probably the dogma of the Cathar religion was derived from Manichaeism although no direct historical link has been established. But the lay converts did not see it as a new religion but a purified form of Christianity.